Intraoperative aberrometry compared to preoperative Barrett True-K formula for intraocular lens power selection in eyes with prior refractive surgery.

To compare the predictive refractive accuracy of intraoperative aberrometry (ORA) to the preoperative Barrett True-K formula in the calculation of intraocular lens (IOL) power in eyes with prior refractive surgery undergoing cataract surgery at the Loma Linda University Eye Institute, Loma Linda, California, USA. We conducted a retrospective chart review of patients with a history of post-myopic or hyperopic LASIK/PRK who underwent uncomplicated cataract surgery between October 2016 and March 2020. Pre-operative measurements were performed utilizing the Barrett True-K formula. Intraoperative aberrometry (ORA) was used for aphakic refraction and IOL power calculation during surgery. Predictive refractive accuracy of the two methods was compared based on the difference between achieved and intended target spherical equivalent. A total of 97 eyes (69 patients) were included in the study. Of these, 81 eyes (83.5%) had previous myopic LASIK/PRK and 16 eyes (16.5%) had previous hyperopic LASIK/PRK. Median (MedAE)/mean (MAE) absolute prediction errors for preoperative as compared to intraoperative methods were 0.49 D/0.58 D compared to 0.42 D/0.51 D, respectively (P = 0.001/0.002). Over all, ORA led to a statistically significant lower median and mean absolute error compared to the Barrett True-K formula in post-refractive eyes. Percentage of eyes within ± 1.00 D of intended target refraction as predicted by the preoperative versus the intraoperative method was 82.3% and 89.6%, respectively (P = 0.04). Although ORA led to a statistically significant lower median absolute error compared to the Barrett True-K formula, the two methods are clinically comparable in predictive refractive accuracy in patients with prior refractive surgery.

Typical electronegative electroretinography and nyctalopia as a presenting feature of systemic malignant melanoma.

We report a unique case of a female who presented with unilateral disk edema, melanoma-associated retinopathy symptoms, and suggestive electroretinography findings preceding a diagnosis of metastatic melanoma of the pelvis. A 63-year-old female presented with complaints of seeing shimmering lights and nyctalopia, and underwent an extensive ophthalmological and electrophysiological examination. Best-corrected visual acuity was 20/20 in both eyes. Visual fields showed relative central scotomata and concentric narrowing. Slit-lamp and fundus examinations were normal. Rod-specific electroretinography responses were severely reduced, with electronegative maximal combined rod-cone responses and delayed cone responses with normal amplitude. Melanoma-associated retinopathy was suspected. Extensive systemic and internal evaluation revealed occult metastatic melanoma of the pelvis of unknown primary site.